Magic mixing angles for doubly heavy baryons

TL;DR

This paper derives the specific magic mixing angles for doubly heavy baryons, which are crucial for understanding their heavy-quark symmetry states and aiding in theoretical model development.

Contribution

It introduces a method to calculate the magic mixing angles for doubly heavy baryons in the $L_ ho=0$ case, linking heavy-quark symmetry states with other quantum states.

Findings

Derived the magic mixing angle for $L_ ho=0$ doubly heavy baryons.

Connected heavy-quark symmetric states with other quantum states via the mixing angle.

Discussed implications for model building of doubly heavy baryons.

Abstract

We study the so-called magic mixing angles for doubly heavy baryons. Defining that a magic mixing angle rotates states with definite $^{2S+1}(l_\lambda)_J$ to make them heavy-quark symmetric states, we derive the magic mixing angle only in the case $L_\rho=0$ between the heavy quark symmetric states with quantum numbers $\left(J, j_\ell\right)$ and the states with $\left(J, s_q+j_\rho\right)=\left(J, \{^4l_\lambda/^2l_\lambda\}\right)$ for a doubly heavy baryon in the standard $\rho-\lambda$ configuration, where $\vec j_\ell=\vec l_\lambda+\vec s_q$, $\vec s_\rho=\vec s_{Q1}+\vec s_{Q2}$, and $\vec j_\rho=\vec s_\rho+\vec L_\rho$. We discuss how this mixing angle affects model building for a doubly heavy baryon.